Chlorophyll and carotenoid patterns of middle eastern date (phoenix dactylifera) fruit at different maturity stages

Abstract

Lipophilic pigments of the date varieties 'Anbra', 'Megadwel', 'Sfwai' and 'Sacai' were characterized by HPLC-DAD-APCI-MSn considering the four progressing ripening stages 'Kimri' (green-ripe), 'Khalal' (breaker), 'Rutab' (brown-ripe) and 'Tamr' (dry-ripe). The prevailing carotenoids in green-ripe and breaker fruits were (all-E)-lutein and (all-E)-β-carotene, in addition to the minor constituents (all-E)-violaxanthin, (all-E)-neoxanthin and (all-E)-zeaxanthin. Most abundant carotenoids in brown-ripe fruits were β-carotene isomers and (all-E)-lutein. Only the early maturity stages contained chlorophylls a and b, summing up to 820-1,282 and 340-878 μg/100 g of fresh weight (FW) in dates harvested at the 'Kimri' and 'Khalal' stage, respectively. Total carotenoids were in the range of 283-411 ('Kimri') and dropped to 230-300 ('Khalal') and 90-231 μg/100 g of FW ('Rutab') with progressing maturation. Among the fully ripe 'Tamr' fruits, merely those harvested from cv. 'Megadwel' contained 30 μg/100 g total carotenoids on a FW basis. The two edible fruit maturity stages 'Khalal' and 'Rutab' represented valuable nutritional sources of the macular carotenoid lutein as well as of β-carotene. At the present concentrations, the latter endows dates with a provitamin A content similar to that of oranges and pineapples.